Treatment of symptomatic peripheral atherosclerotic disease with a rotational atherectomy device

The role of atherectomy in BTK lesions. A systematic review

INTRODUCTION

To evaluate the current role of atherectomy techniques (ATH) in treatment of peripheral arterial disease (PAD) at below the knee (BTK) arteries.

EVIDENCE ACQUISITION

The PubMed and Embase were searched (last search on 11 September 2021) for studies reporting on the early and mid-term outcomes of ATH in BTK vessels. Analysis included the data from six studies, with a total of 1062 PAD patients treated with various ATH techniques. We compared them the ATH outcomes with the contemporaneous outcomes of plain balloon angioplasty alone or with bailout stenting. Early safety and efficacy were accessed with perioperative and 30-day technical success rate, which included the primary patency of the treated BTK arterial segment. Evaluation of clinical performance was based on target limb revascularization (TLR) and on major limb adverse events (MALEs) rates.

EVIDENCE SYNTHESIS

The current body of literature mainly includes retrospective observational studies, and the level of derived evidence is low. The mean perioperative and 30-day technical success rate was 87.3%. The mean reported TLR and MALEs rates at 12 months were 6.6% and 4.7% respectively. The relevant rates in studies reporting at 24 months were 24.3% and 31.7% while in studies reporting at 36 months the rates were 37.0% and 23.0% respectively.

CONCLUSIONS

Based in low-quality evidence, it seems that ATH in BTK vessels has a high safety, high efficacy profile and durable outcomes at 12 months. In the midterm, the clinical success of ATH is compromised by increased TLR and MALEs rates. Comparison of ATH with other endovascular techniques in BTK treatment of PAD shows a slight lead of ATH at 1-year and equivalent clinical performance in the mid-term. Overall, ATH has a significant and potentially predominant role in treatment of BTK vessels.

Effects of high-speed rotational atherectomy in peripheral artery disease patients with calcified lesions: a retrospective multicenter registry

Calcified lesions still remain a technical challenge even in the treatment of infrainguinal artery disease. The aim of this retrospective, multicenter observational study was to investigate interventional outcomes of a high-speed rotational atherectomy device (Rotablator™) and to compare clinical outcomes in patients who underwent Rotablator and those who did not even after failed balloon angioplasty because of underlying calcified lesions. This study enrolled patients who underwent Rotablator (Rota group) and those who did not (Non-rota group) between January 2010 and 2014 December at 12 hospitals. A total of 67 limbs and 68 lesions in 65 patients were included (Rota group; 54 limbs and 55 lesions in 52 patients, Non-rota group; 13 limbs and 13 lesions in 13 patients). In the Rota group, a technical success rate was 94.5% with a complication rate of 1.8%, and all lesions underwent subsequent postdilatation following the adjunctive use of Rotablator, and approximately half of above-the-knee lesions underwent stent implantation. The Rota group had a significantly lower clinically driven reintervention rate at 12 months than the Non-rota group (26.5% vs. 58.3%, respectively, p = 0.046). In addition, Rota group showed a trend toward a higher amputation-free survival compared to the Non-rota group at 1 month (Rota; 98.0% vs. Non-rota; 84.6%, respectively, p = 0.10). Rotablator was used as an adjunctive device with a high technical success and a low complication rates, and Patients who underwent Rotablator yielded a significantly lower clinically driven reintervention rate at 12 months compared to those who did not even after failed balloon angioplasty.

Application of rotational atherectomy for a calcified superficial femoral artery lesion

A 78-year-old man on dialysis with a history of femoro-popliteal bypass grafting of his right superficial femoral artery was presented with a recurrence of intermittent claudication. Angiography revealed new heavily calcified stenosis located distal to the anastomosis of the graft. A guide wire was crossed the lesion, however, a balloon catheter could not pass. Rotational atherectomy with Rotablator enabled the balloon to cross the lesion with full dilatation. Due to residual stenosis and dissection, a stent was implanted. Final angiogram showed no residual stenosis with TIMI 3 flow. The patient remained free of symptoms during the 1-year follow-up.

[Percutaneous mechanical atherectomy for treatment of peripheral arterial occlusive disease]

Peripheral arterial occlusive disease (PAOD) is still an extremely important politico-economic disease. Diverse treatment procedures exist but the pillars of therapy are changes in lifestyle, such as nicotine abstinence and walking exercise as well as drug therapy. Further therapy options are considered after conventional procedures have been exhausted. These further options consist of improvement of the blood supply by surgical or minimally invasive procedures. The latter therapy options include balloon dilatation and stenting as the most widely used techniques. More recent techniques also used are cryoplasty, laser angioplasty, drug-coated stents or balloons as well as brachytherapy or atherectomy, whereby this list makes no claims to completeness. The multitude of different treatment methods emphatically underlines the fact that no resounding success can be achieved with one single method. The long-term results of both balloon dilatation and stenting techniques show a need for improvement, which elicited the search for additional methods for the treatment of PAOD. Atherectomy represents such an alternative method for treatment of PAOD. Basically, the term atherectomy means the removal of atheroma tissue. For percutaneous atherectomy, in contrast to surgical procedures, it is not necessary to create surgically access to the vessel but accomplishes the atherectomy by means of dedicated systems via a minimally invasive access. There are two basic forms of mechanical atherectomy: directional and rotational systems.

Assessment of the Histological Characteristics of Coronary Arterial Plaque With Severe Calcification

BACKGROUND

Several studies have shown that rotational atherectomy (RA) is associated with higher rates of the slow-flow phenomenon and that ablated particles may be the possible cause. Intravascular ultrasound (IVUS) has an intrinsic limitation in assessing plaque morphology behind the calcification because of acoustic shadowing. Therefore, the purpose of this study was to investigate plaque characteristics behind severe calcification by histological examination.

METHODS AND RESULTS

One hundred eight coronary arterial segments from 40 human cadavers (24 males, 16 females, mean age 74+/-7 years) were examined. Serial images of IVUS were obtained and 18 severe calcified lesions were collected. Experienced observers quantitatively analyzed the lesions by computerized planimetry for fibrous, fibrofatty, calcification, and necrotic tissue area. Histologically, 15 of 18 severely calcified lesions (83%) had an extensive necrotic tissue containing large numbers of cholesterol crystals and microcalcifications; 16 of same 18 severely calcified lesions (89%) had fibrofatty tissue as well as calcification. The necrotic tissue occupied 14+/-13% and fibrofatty tissue occupied 13+/-11% of severely calcified lesions.

CONCLUSION

Necrotic core and fibrofatty tissue components "hidden" behind calcification might cause emboli-induced thrombus formation and distal flow disturbance during RA.

Retrograde rotablator in limb salvage: a new technique using an open approach

Conventional vascular surgery and balloon angioplasty have poor results in severe and diffuse atherosclerotic disease of the infrapopliteal arteries. High-speed rotational atherectomy (Auth Rotablator) has not succeeded either, because of poor long-term patency and the non-reflow phenomenon. We report a case of limb salvage with long occlusion of the three infrapopliteal vessels. The anterior tibial artery was treated with retrograde Auth Rotablator atherectomy by an open approach through the pedal artery, resulting in full patency of the anterior tibial artery and healing of the skin lesions. The microparticulate debris from the ablation was drained out through the pedal arteriotomy, avoiding the complications associated with conventional antegrade high-speed rotational atherectomy.

Effect of intracoronary nicorandil administration on preventing no-reflow/slow flow phenomenon during rotational atherectomy

A major limitation of the rotational atherectomy (RA) procedure is the occurrence of the no-reflow/slow flow phenomenon and the optimal strategy is still evolving. Recent clinical studies have demonstrated the beneficial effects of nicorandil, an adenosine triphosphate (ATP)-sensitive potassium channel opener, on no-reflow in patients with acute myocardial infarction. The purpose of this study was to evaluate the effect of nicorandil on no-reflow/slow flow phenomenon during RA procedures. Sixty-one patients who underwent RA of complex coronary lesions were randomly divided into 2 groups: (i) nicorandil cocktail (n=24 patients, 37 lesions) and (ii) verapamil cocktail (n=37 patients, 63 lesions). In each group, the drug cocktail mixed with pressurized saline was infused through the 4Fr Teflon sheath of the rotablator system during the RA procedure. In the nicorandil group, the drug cocktail consisted of 24 mg of nicorandil, 5 mg of nitroglycerin, and 10,000 U of heparin. In the verapamil group, the drug cocktail consisted of 10 mg of verapamil, 5 mg of nitroglycerin, and 10,000 U of heparin. Baseline and procedure characteristics did not differ between the 2 groups. RA was performed successfully, and death, Q-wave myocardial infarction, or emergency coronary artery bypass surgery did not occur in any patients. The no-reflow/slow flow phenomenon was observed in 11/63 (17.4%) lesions of the verapamil group, but in only 1/37 (2.7%) lesions of the nicorandil group (p=0.03). No untoward complications were observed during nicorandil infusion. These data indicate that the intracoronary continuous infusion of nicorandil during RA procedures is easy and safe, and prevents no-reflow/slow flow phenomenon more effectively than infusion of verapamil.

Results of endovascular superficial femoral endarterectomy

BACKGROUND

Endovascular superficial femoral artery (SFA) endarterectomy with a ring stripper/cutter and distal stenting has been suggested to have a patency comparable with above-knee bypass surgery. We report our initial experience with this technique.

METHODS

Seventeen patients (13 men and 4 women; mean age, 64 years) with SFA occlusion and above-knee popliteal reconstitution underwent attempted remote endarterectomy with a ring cutter system combined with primary stenting of the distal end point. Analysis was performed in a prospective manner with patency rates determined by Kaplan-Meier life-table analysis.

RESULTS

The indication for operation was claudication in 8 patients, rest pain in 6, and tissue loss in 3. Initial technical success was achieved in 11 patients (65%). Reasons for technical failure included SFA perforation (4), inability to traverse a calcified/diseased segment (1), and inability to retract/remove the ring cutter (1). Life-table analysis of all patients revealed a primary patency at 1 year of 26% +/- 11%. Primary-assisted patency was 38% +/- 12% at 1 year, with 59% of patients ultimately requiring surgical bypass grafting. In patients in whom initial technical success was achieved, the 1-year primary and primary-assisted patency rates were 40% and 59%, respectively. There were four reocclusions requiring surgical revascularization with below-knee popliteal (2) or tibial (2) bypass grafting, 1 symptomatic restenosis requiring repeat angioplasty, and 1 symptomatic restenosis treated conservatively.

CONCLUSION

The results of endovascular SFA endarterectomy were disappointing, with technical success in less than two thirds of patients and a 1-year primary patency of only 26%. Remote SFA endarterectomy appears less effective than above-knee femoropopliteal bypass grafting, and after early failure, patients may require more distal revascularization for limb salvage.

Treatment of infrapopliteal occlusive disease by high-speed rotational atherectomy: initial and mid-term results

PURPOSE

To assess the effectiveness and patency rates of high-speed rotational atherectomy (HSRA) for the treatment of infrapopliteal arterial occlusive disease.

MATERIAL AND METHODS

During an 18-month period, a total of 19 infrapopliteal lesions in 15 consecutive patients were treated primarily by HSRA with use of the Rotablator device. Patients were followed up with documentation of clinical symptoms, standardized treadmill exercise, and Doppler sonography at 1, 3, and 6 months. Control angiography was performed 6 months after primary treatment.

RESULTS

HSRA was initially successful in 14 of 15 patients, yielding an initial technical success rate of 94%. Percutaneous treatment induced an improvement of the ankle-brachial index (ABI) from 0.6 +/- 0.09 to 0.86 +/- 0.2 after intervention (P < .0001). Doppler analysis showed a mean ABI of 0.85 +/- 0.2 (P < .001) at 1 month, 0.72 +/- 0.2 (P = .012) at 3 months, and 0.7 +/- 0.2 (P = .08) at 6 months after initial therapy. Although six patients were lost to follow-up at various times, control angiography at 6 months was carried out in nine of 15 patients, allowing direct assessment of 12 of 19 treated lesions. Among six high-grade restenoses and five total occlusions in the treated vascular segments, only one arterial lumen (of 12) remained patent without presenting a hemodynamically relevant restenosis. These results led to termination of the study.

CONCLUSION

Although HSRA for the treatment of infrapopliteal occlusive disease yields a very high initial technical success rate, mid-term results are extremely poor. Therefore, HSRA cannot be recommended for primary treatment of this type of lesion.

Effect of Rotablator atherectomy and adjunctive balloon angioplasty on coronary blood flow

BACKGROUND

The purpose of this study was to assess serial changes in coronary blood flow velocity before and after Rotablator atherectomy and after adjunctive percutaneous transluminal coronary angioplasty (PTCA). Since Rotablator atherectomy results in luminal enlargement by plaque pulverization and distal embolization, improvement in coronary blood flow could be attenuated despite luminal enlargement.

METHODS AND RESULTS

Intracoronary Doppler blood flow velocity measurements were obtained with a Doppler Flowire. Basal average peak velocity (bAPV), hyperemic APV (hAPV), diastolic/systolic velocity ratio (DSVR), and coronary flow reserve (CFR) were assessed before intervention, after Rotablator, and after adjunctive PTCA. Complete clinical, angiographic, and Doppler data were obtained in 22 patients. There was a small but significant difference (P = .02) in resting heart rate and mean arterial pressure before and after Rotablator and after adjunctive PTCA. Minimum lumen diameter increased from 0.8 +/- 0.1 to 1.5 +/- 0.2 to 2.0 +/- 0.1 mm (P < .001), corresponding to decreases in diameter stenosis from 72 +/- 3% to 41 +/- 4% to 36 +/- 3% (P < .001). Although bAPV, hAPV, and DSVR increased significantly (P < .001), CFR remained abnormally low in 19 of 22 patients (despite an increase from baseline to post-PTCA). hAPV > 30 cm/s was the best Doppler correlate of angiographic success.

CONCLUSIONS

Rotablator atherectomy and adjunctive PTCA significantly improve distal coronary blood flow velocity and DSVR but not CFR. Failure to normalize CFR could be secondary to parallel increases in bAPV and hAPV, "acquired" microvascular disease due to distal microembolization or spasm, and/or angiographically inapparent dissection or residual stenosis. Adjunctive PTCA contributes significantly to the overall physiological benefit of a combined procedure.

Prevalence and timing of regional myocardial dysfunction after rotational coronary atherectomy

OBJECTIVES

This study aimed to evaluate the prevalence and time course of wall motion abnormalities associated with rotational coronary atherectomy.

BACKGROUND

Although initial clinical studies found evidence of transient wall motion abnormalities after rotational coronary atherectomy, the prevalence and duration of these wall motion abnormalities are unknown.

METHODS

Using simultaneous echocardiography, we prospectively evaluated 22 patients undergoing rotational atherectomy and compared their wall motion abnormalities with those of 10 patients undergoing coronary angioplasty alone. The extent of wall motion abnormality was quantified and plotted against time to produce curves of abnormal wall motion development and recovery for the two groups.

RESULTS

The cumulative ischemic time was similar for the two groups ([mean +/- SD] 10.3 +/- 6 min for rotational atherectomy vs. 9.6 +/- 4.2 min for coronary angioplasty, p = 0.73). The rate of return to baseline function was significantly lower in the rotational atherectomy group than in the coronary angioplasty group (rotational atherectomy rate constant 0.069 +/- 0.079/min vs. coronary angioplasty rate constant 1.250 +/- 0.47/min, p = 0.0001). The mean time to recovery of baseline wall motion in the rotational atherectomy group (153 min, 95% confidence interval [CI] 6.5 to 3,600) was significantly longer than in the coronary angioplasty group (2.6 min, 95% CI 1.3 to 5.5, p = 0.0001). Rotational atherectomy burr time was longer in the patients who developed myocardial infarction than in those without myocardial infarction (4.7 +/- 2.4 vs. 3 +/- 1.4 min, p = 0.045).

CONCLUSIONS

Transient wall motion abnormalities are common after rotational coronary atherectomy and have a longer duration than those observed after coronary angioplasty. This disparity may be a consequence of differences in the mechanisms by which rotational coronary atherectomy and coronary angioplasty produce their effect.

The history of interventional cardiology: cardiac catheterization, angioplasty, and related interventions

The histories of cardiac catheterization, angioplasty, and other catheter interventions are spectacular journeys marked by undeterred genius, serendipity, and the vindication of the scientific method. Cardiac catheterization began with Hales's 1711 equine biventricular catheterization, other early experimental catheterizations in the nineteenth century, and Forssmann's dramatic 1929 right-heart self-catheterization. Cournand, Richards, and others finished unlocking the right heart in the 1940s; Zimmerman, Cope, Ross, and others unlocked the left heart in the 1950s; and the coronary arteries were inadvertently unlocked by Sones in 1958, leading to the advent of percutaneous femoral coronary angiography by Judkins and by Amplatz in 1967. Dotter's accidental catheter recanalization of a peripheral artery in 1963 ushered in the era of intervention, crowned by Gruentzig's balloon angioplasty in the mid-1970s and leading to today's panoply of devices used percutaneously to revascularize the coronary arteries in a variety of clinical settings.

Rotational atherectomy multicenter registry: acute results, complications and 6-month angiographic follow-up in 709 patients

OBJECTIVES

The purpose of this study was to describe data collected for an industry-sponsored multicenter registry of rotational atherectomy.

BACKGROUND

Several new devices are in use or under development for coronary atherectomy. The clinical role for each is in part defined by descriptive registry data.

METHODS

We describe results in 709 consecutive patients undergoing 743 procedures representing 874 lesions. The majority of lesions were in the left anterior descending coronary artery. Lesion morphology was described as eccentric (61.1%), calcified (32%), tortuous (26.6%) and long (24.9%), with previous intervention in 32.7%.

RESULTS

Overall procedural success rate, including lesions treated with rotational atherectomy alone and with balloon angioplasty was 94.7% and did not vary between lesion type, location, characteristics or severity. Previously treated lesions had a significantly higher success rate (97.4%, p = 0.04) than new lesions. Major complications, including death 0.8% (95% confidence interval [CI] 0.3% to 1.7%), Q wave myocardial infarction 0.9% (95% CI 0.4% to 1.9%) and emergent coronary artery bypass surgery 1.7% (95% CI 0.9% to 3.0%), were similar to other reported devices and were associated with length and number of lesions treated. Non-Q wave myocardial infarction occurred in 3.8% of patients and was significantly associated with female gender and history of previous myocardial infarction. Abrupt occlusion occurred in 3.1% of patients and was significantly associated with bifurcated lesions and the use of adjunctive therapy. Angiographic evidence of dissection was seen in 10.5% (95% CI 8.3% to 12.7%) of patients and was significantly associated with more complex lesions, such as eccentric, long, calcified and American College of Cardiology/American Heart Association type C lesions. Overall restenosis rate was 37.7%, determined with 6-month angiography, representing 64% of treated lesions. Higher restenosis rates were associated only with poorer initial treatment outcome, diabetes and lower follow-up angiographic rate per reporting center.

CONCLUSIONS

Rotational atherectomy appears to be a safe method of treatment with a high success rate in a broad spectrum of lesion types, with restenosis rates similar to other techniques. Further conclusions will require randomized trials.

High-frequency rotational ablation following failed percutaneous transluminal coronary angioplasty

Percutaneous transluminal coronary angioplasty (PTCA) failed in 29 of 1,150 patients (2.5%) after successful passage of the guide wire. The reasons for failure were inability to pass the lesion with a balloon in 28 patients and inability to dilate the lesion in 1 patient. In these patients (15 stenoses and 14 chronic occlusions) rotational ablation was performed. We were able to pass the burr through the lesion in all of them, resulting in a reduction of diameter stenosis from 87 +/- 15 to 51 +/- 18%. Rotational ablation alone was initially successful (stenoses reduction > 20% and residual stenoses < 50%) in 15 of 29 (52%) patients. Additional PTCA was performed in 21 of 29 (72%) patients, in 8 to optimize the initially successful result and in 13 because the outcome was unsatisfactory. After dilatation the diameter stenosis was reduced to 41 +/- 14% immediately after the procedure and to 36 +/- 13% at 24 hr control. Overall success was achieved in 21 of 29 (72%) patients immediately after the procedure and in 26 of 29 (90%) patients at 24 hr control. No acute major complications occurred. We conclude that rotational ablation can be used as a safe and effective alternative when PTCA is not successful.

Directional atherectomy with the Omnicath: a unique new catheter system

Omnicath is a directional atherectomy catheter that employs deflecting nontraumatizing wires to anchor the cutting window at the atherectomy site. This anchoring system regulates the depth of cut and provides directional control and distal perfusion. The system continuously removes debris through a suction port from the operative site. To demonstrate the performance of the device, the Omnicath was tested in the external iliac arteries of ten atherosclerotic Hanford miniature swine in which concentric and eccentric lesions were induced. Five animals were sacrificed 3 days after atherectomy; the remaining five animals were sacrificed 6 weeks after the procedure. The acute histology demonstrates depth of cuts varying from partial plaque removal to near full thickness removal of the arterial wall. Histologic sections of the 6 week follow-up group demonstrated minimal healing response. The anchoring wires did not induce either acute injury or neointimal proliferation in the 6 week follow-up period. In conclusion, the Omnicath permits effective and safe atherectomy in this investigative model.

Hemolytic effect of the Amplatz thrombectomy device

PURPOSE

The hemolytic effect of the Amplatz thrombectomy device (ATD) was evaluated in nine dogs and in nine patients.

MATERIALS AND METHODS

The device was activated for 1-2 minutes in the abdominal aorta, inferior vena cava, or femoral artery of nine dogs. The device was activated for 1-4 minutes in the nine patients in occluded lower extremity bypass grafts (n = 5), native superficial femoral artery (n = 1), a pulmonary artery embolus (n = 1), a portocaval shunt (n = 1), and an iliac vein stent (n = 1). Patients were examined for laboratory evidence of hemolysis following mechanical thrombectomy.

RESULTS

In all dogs haptoglobin level decreased, free hemoglobin level in the plasma increased, and hemoglobinuria was present. There was no change in renal function. The level of haptoglobin decreased and the level of plasma free hemoglobin increased in eight patients, with hemoglobinuria detected in one. More hemolysis was observed in the animals than in the patients.

CONCLUSION

The ATD has a definite transient hemolytic effect. Until further studied, it should not be used in children and should be used with caution in patients who are anemic, hypoxemic, or have potentially reversible renal insufficiency. Activation time should be monitored closely because hemolysis probably increases with increasing activation time.

High-speed rotational ablation (Rotablator) for unfavorable lesions in peripheral arteries

A strategy of using a single, conservatively sized percutaneous transluminal rotational ablation device with or without adjunctive balloon angioplasty was employed in 18 vessels in 17 patients selected because of unfavorable lesion morphology for balloon angioplasty alone. Fifteen patients had lower extremity occlusions and/or heavily calcified lesions and two patients had ostial renal artery stenoses. We were able to achieve a 94% (17/18 lesions) technical success rate, and a 94% (16/17 patients) clinical success rate. In the patients with lower extremity lesions, the baseline ankle-brachial blood pressure index increased from 0.55 +/- 0.15 to 0.90 +/- 0.19 (p < .001) 1 day after the procedure. Follow-up at 6.8 +/- 2.8 months revealed clinical evidence of restenosis in only one patient. We conclude that a cost-effective strategy of treating unfavorable lesions with a single Rotablator burr and adjunctive balloon angioplasty is safe and effective.

Sequential intravascular ultrasound characterization of the mechanisms of rotational atherectomy and adjunct balloon angioplasty

OBJECTIVES

The purpose of this study was to use sequential intravascular ultrasound imaging before intervention, after rotational atherectomy and after adjunct balloon angioplasty to characterize the mechanisms of lumen enlargement after each.

BACKGROUND

Rotational atherectomy uses a high speed, rotating, diamond-tipped elliptic burr to abrade atherosclerotic plaque to increase lumen size. In vitro studies have shown that high speed rotational atherectomy selectively abrades hard, especially calcified, plaque elements. However, rotational atherectomy procedures usually require adjunct balloon angioplasty.

METHODS

Forty-eight lesions in 46 patients were treated with rotational atherectomy followed by adjunct balloon angioplasty in 44. Quantitative coronary arteriographic and intravascular ultrasound measurements of the target lesion were made before intervention, after rotational atherectomy and after balloon angioplasty.

RESULTS

Before intervention, target lesion external elastic membrane area measured 17.3 +/- 5.9 mm2, lumen area measured 1.8 +/- 0.9 mm2 and plaque plus media area measured 15.7 +/- 4.1 mm2. After rotational atherectomy, lumen area increased, plaque plus media area decreased, arc of target lesion calcium decreased and 26% of the target lesions had dissection planes. After adjunct balloon angioplasty, external elastic membrane area increased, lumen area increased, plaque plus media area did not change and 77% of the target lesions had dissection planes. Arterial expansion was seen in 80% of lesions. The pattern of dissection plane location, which was predominantly within calcified plaque after rotational atherectomy, became predominantly adjacent to calcified plaque after adjunct balloon angioplasty (p = 0.008).

CONCLUSIONS

Sequential intravascular ultrasound imaging shows that high speed rotational atherectomy causes lumen enlargement by selective ablation of hard, especially calcific, atherosclerotic plaque with little tissue disruption and rare arterial expansion. Adjunct balloon angioplasty further increased lumen area by a combination of arterial dissection and arterial expansion, especially of compliant, noncalcified plaque elements.

High frequency rotational ablation: an alternative in treating coronary artery stenoses and occlusions

OBJECTIVE

To prove the safety and effectiveness of high frequency rotational ablation of coronary artery stenoses and occlusion in humans.

SUBJECTS

106 patients with symptoms (91 men, 15 women) who had 67 significant stenoses, mainly types B and C, and 46-chronic occlusions.

MAIN OUTCOME MEASURES

Mean change in diameter stenosis after rotational angioplasty alone and in combination with percutaneous transluminal coronary angioplasty immediately after treatment and 24 hours and six months later; restenosis rates at six months; complication of treatment.

RESULTS

Rotational ablation could not be used in five stenoses and 16 chronic occlusions because of inability to reach or cross the lesion with the Rotablator guide wire. In four cases rotational ablation failed. Initial angiographic and clinical success by rotational ablation was achieved in 40 of the 67 stenoses (60%) and in 18 of the 46 chronic occlusions (39%). Additional balloon angioplasty was performed in 45 patients, increasing the success rates to 79% and 54%, respectively. In the 62 stenoses treated by rotational ablation the angiographic diameter stenoses were reduced from 76% (SD 14%) to 32% (14%) after Rotablator treatment alone and from 75% (11%) to 33% (17%) with additional balloon angioplasty. In the 30 chronic occlusions treated by rotational ablation the angiographic diameter stenoses were reduced to 38% (18%). At six months angiographic restenosis was evident in nine of the 25 (36%) stenoses treated with rotational ablation alone, in seven of the 22 (32%) stenoses treated with rotational and balloon angioplasty, and in 14 of the 24 (58%) chronic occlusions. There were no procedural deaths and two patients (2%) underwent emergency coronary artery bypass grafting. Although no transmural infarction occurred, there were five (6%) non-Q wave infarctions (two embolic side branch occlusions, two subacute occlusions, and one acute occlusion). Clinically insignificant slight increases in creatine kinase activity were seen in five patients (6%). Severe coronary artery spasm unresponsive to medical treatment was provoked in seven cases (8%).

CONCLUSIONS

High frequency rotational ablation is a safe and effective method for treating type B and C coronary artery lesions with results comparable to percutaneous transluminal coronary balloon angioplasty. The combined use of rotational ablation and balloon angioplasty is feasible and is necessary in about half of all procedures, in most cases because the lumen created by the biggest burr is too small.

Options for percutaneous coronary and peripheral revascularization

Angioplasty has become an established treatment for both coronary and peripheral atherosclerosis, and a number of new techniques and devices promise to improve the results of percutaneous intervention during the coming decades. It is likely that balloon angioplasty will remain the percutaneous treatment of choice for both coronary and peripheral intervention; however, we look with hope toward the development of new devices that will expand the role of percutaneous angioplasty and improve the long-term success of these procedures. As technical expertise grows with the new procedures, prospective randomized trials comparing them with standard PTCA will be required to enable physicians to judge their clinical utility.

Endovascular surgery for peripheral arterial occlusive disease. A critical review

Endovascular surgery is a new multidisciplinary field that applies the recently innovated techniques of angioscopy, intraluminal ultrasound, balloon angioplasty, laser, mechanical atherectomy, and stents. This field can be defined as a diagnostic and therapeutic discipline that uses catheter-based systems to treat vascular disease. As such, it integrates the subspecialties of vascular surgery, interventional radiology, interventional cardiology, and biomedical engineering for the common purpose of improving arterial hemodynamics. Endovascular surgery offers many potential benefits: long incisions are replaced with a puncture wound, the need for postoperative intensive care is significantly reduced, major cardiac and pulmonary complications from general anesthesia are side stepped, and the dollar savings could be dramatic as the need for intensive care unit and in-hospital stay diminishes. Despite these technological advancements, endovascular surgery is still in its infancy and currently has limited applications. This review provides an updated summary of endovascular surgery today and addresses some of the obstacles still preventing its widespread use.

Rotational ablation of coronary artery lesions using single, large burrs

Previous clinical use of the Rotablator in coronary artery disease has involved a sequential increase in burr sizes up to 2 mm in diameter and has often utilized balloon adjunct to achieve an optimal result. We report our experience and describe our technique using a single, large burr (2.25, 2.5, or 2.75 mm diameter) without balloon assistance. The burr size was selected to approximate 70-90 percent of the apparent normal lumen diameter. Thirty-one patients with 36 lesions of complex morphology (eccentric, irregular, calcified, ulcerated, at bends, at bifurcations, completely occluded, as well as balloon failures) were successfully treated with the Rotablator. Results were assessed by computerized quantitative angiography. The percent diameter stenosis (mean +/- SD) for the group was reduced from 69.8 +/- 11.3% to 30.9 +/- 10% (p less than 0.001). The mean absolute diameter stenosis increased from 0.9 +/- 0.3 mm to 2.2 +/- 0.3 mm (p less than 0.001). Angiographically visible dissections were seen in 4 patients and were uncomplicated in 2. One patient had a non-Q-wave myocardial infarction. A fourth patient had a presumed acute occlusion 36 hr after the procedure, necessitating emergency bypass surgery, but without Q waves on the electrocardiogram or wall-motion abnormalities on the echocardiogram. Nitroglycerin was infused through the Rotablator catheter and has considerably lowered the degree and frequency of spasm. No other acute complications occurred. The mean procedure time using a single burr was shorter than when multiple burrs were used: 56.5 vs. 97.3 min, respectively (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of rotational atherectomy in normal canine coronary and diseased human cadaveric arteries: potential for plaque removal from distal, tortuous, and diffusely diseased vessels

To test the hypothesis that tortuous, diseased vessels could be successfully treated with a flexible rotational atherectomy device we evaluated the BARD atherectomy device with quantitative angiography and histology in normal canine coronary arteries and diseased human below-knee amputation specimens. The mid left anterior descending and the circumflex vessels were treated in 4 dogs serially with 1 wk separating treatments. The acute and follow-up anterior descending artery size was unchanged (1.41 mm before, 1.39 mm after, and 1.59 mm at 1 week). Similar findings were obtained in the circumflex vessels. In 4 adult human amputated legs, diseased peroneal or tibial arteries were treated with a significant reduction in the percent luminal diameter stenosis from 62.75 prior to intervention to 36.5 following intervention (p = 0.021). The luminal diameter increased from 0.81 to 1.54 mm (p = 0.06). In 2 canine arteries there was histologic evidence of localized perforation of the arterial wall, but there was no angiographic evidence of perforation or dissection and no significant myocardial necrosis in the distribution of the treated vessels at 1 wk. The majority of the diseased human vessels demonstrated smoothly cut atheromas with sparing of the media. The rotational atherectomy catheter system holds promise for removal of plaque in relatively small, diffusely diseased, tortuous vessels.

Successful rotational coronary ablation following failed balloon angioplasty

Rotational coronary ablation was utilized in two cases in which balloon angioplasty initially failed. In both cases, the balloon could not be fully expanded despite using high (18 Bar) inflation pressure. Rotational coronary ablation debulked the lesion, in each instance, and permitted successful balloon angioplasty to be accomplished without difficulty. These cases illustrate the point that complementary deployment of devices may not only improve the primary success of percutaneous coronary interventions, but also may widen its scope.

Acute angiographic and clinical outcome of high speed percutaneous rotational atherectomy (Rotablator)

Percutaneous rotational atherectomy (Rotablator), a high speed (greater than 100,000 RPM) rotational burr, was used successfully in 38 of 43 patients (88%) (mean age: 65 +/- 7 years) with 82 lesions (71 stenoses and 11 occlusions). The clinical indications were claudication (84%), nonhealing ulcer (7%), and renovascular hypertension (7%). Rotablation was successful in 78 of 82 lesions (95%): 68 of 71 (96%) stenoses (12 of 12 iliac, 11 of 11 femoral, 7 of 8 popliteal, 36 of 37 tibial, and 2 of 3 renal arteries; 60% of lesions were diffuse, i.e., greater than or equal to 4 cm in length), and 10 of 11 (91%) occlusions (5 of 6 femoral, 1 of 1 popliteal, 3 of 3 tibioperoneal, 1 of 1 brachial artery). The Rotablator significantly (p less than 0.001) reduced the arterial obstruction (stenoses: 85 +/- 11% to 12 +/- 12%); occlusions: 100% to 25 +/- 10%). The effective final burr size for arteries varied at 3.5-4.5 mm for renal, 3.0-3.5 mm for femoral, and 2.0-3.0 mm for brachial and tibial. Complications included gross hemoglobinuria without sequelae in 27 patients (63%), groin hematoma in 10 (23%), arterial spasm in 10 (23%), and arterial bypass in 2 (5%). The Rotablator was successfully used, without concomitant conventional balloon angioplasty, to open arterial lesions with excellent angiographic results in both diffuse and segmental peripheral vascular disease. There was gratifying patient clinical improvement.

Angiographic follow-up and clinical outcome of 126 patients after percutaneous directional atherectomy (Simpson AtheroCath) for occlusive peripheral vascular disease

Angiographic and clinical follow-up data were obtained in 115/126 patients who underwent directional atherectomy for peripheral vascular disease; of the 126, ten were excluded for appropriate reasons and one was lost to follow-up. Thus, 115/116 successful atherectomy patients (99%) had follow-up of 182/213 lesions (86%): 74 patients (64%) with angiography (mean time 5.4 mon), and 41 patients (36%) clinically. One hundred twenty-eight of 183 lesions (70%) had angiographic follow-up; the lesion recurrence as a stenosis or as an occlusion was 53%. Lesion distribution did not differ between angiography and clinical follow-up groups: nearly 85% were within the superficial femoral or popliteal arteries. Despite data stratification, angiographic follow-up indicated that patients after successful directional atherectomy, at a mean follow-up time of 5 mos, have more than a 50% lesion recurrence rate. Although directional atherectomy (Simpson AtheroCath) utilizing present techniques has excellent primary success and acceptable complication rates, angiographic follow-up statistics are bothersome.

Ex-vivo results using a new pullback atherectomy catheter (PAC)

In order to evaluate the feasibility of performing definitive atheromatous plaque removal using a novel retrograde cutting (Pullback) atherectomy catheter, pullback atherectomy was performed in 13 severely diseased cadaveric superficial femoral arteries. All experiments were performed using cadaver tissue either mounted in a perfusion/mounting chamber (n = 10) or left in situ (n = 3). In general, a single cut was made with each of three sequentially larger atherectomy catheters (2.5 mm, 3.0 mm, and then 3.5 mm devices). The results were evaluated by angiography and by light microscopy. Nine of the 13 experiments were performed in totally occluded vessels. The mean pre-atherectomy stenosis (all specimens) was 95 +/- 3%, with a final mean postatherectomy stenosis of 21 +/- 5%. There was one vessel performation. We conclude from these preclinical studies that retrograde atherectomy with the Pullback Atherectomy Catheter is a feasible means of performing definitive atherectomy. Despite the promising potential of retrograde atherectomy, little can be said with certainty about the clinical utility of such a device at this early stage.

Peripheral atherectomy: experimental results with a new device

The size of present rotational atherectomy devices is limited in part by a tendency to produce vessel torsion. The authors designed and investigated a large-bore rotational atherectomy device for peripheral atherectomy in a single pass without significant torsion. A plaque was retrieved from 36 of 40 cadaveric iliac arteries. The mean plaque size was 8.4 x 3.9 mm, and the average number retrieved per artery was two. Thirty of 34 severely calcified arteries were treated successfully. Effluent study revealed no distal embolization; however, six perforations and four dissections occurred. Preliminary results suggest that a cutting surface with a relatively large diameter can be designed to be effective without producing vessel torsion. Changes in future designs will include added flexibility and expandable cutting surfaces to enhance safety and minimize entry diameter.

In vivo ultrasound arterial recanalization of atherosclerotic total occlusions

The purpose of this study was to assess the potential of intraarterial ultrasound for in vivo recanalization of atherosclerotic total occlusions. Ultrasound energy at a frequency of 20 kHz was applied with a prototype solid wire probe to 12 surgically implanted occluded human atherosclerotic arterial xenografts, 9 of which were calcified, as well as to the intimal surface of 12 normal canine arteries. In both the normal canine arteries and the atherosclerotic occluded xenografts, there was no angiographic evidence of vasospasm, thrombosis or arterial dissection. Eleven of the 12 atherosclerotic complete arterial occlusions were resistant to passage of a conventional guide wire or probe without ultrasound energy. However, the occlusions were recanalized after administration of 15 s to 4 min (mean 1.5 +/- 1.3 min) of intermittent ultrasound energy. After ultrasound, 8 of the 12 vessels underwent balloon angioplasty. Angiographic residual stenosis after ultrasound alone was 62 +/- 24% and after combined ultrasound and balloon angioplasty, 29 +/- 13%. Although routine angiography did not reveal arterial emboli, high resolution cut films did demonstrate a few distal nonocclusive thrombi of a size similar to that reported with other recanalization methods. Histologic studies demonstrated changes similar to those after balloon angioplasty, with focal cracking of the fibrotic and calcified plaque. The findings demonstrate that ultrasound energy applied through a catheter delivery system can be used in vivo to open completely obstructed atherosclerotic vessels. These studies suggest that it might be clinically feasible to use the ultrasound probe to create a lumen, allowing subsequent balloon dilation.

Percutaneous ultrasonic angioplasty:initial clinical experience

Percutaneous catheter-delivered ultrasound energy for arterial recanalisation was applied in eight patients with peripheral vascular disease. Four patients had severe claudication with total occlusion and four high-grade stenosis in a superficial femoral or popliteal artery. A prototype ultrasound probe, with a frequency of 20 kHz and a power output of 20-35 W/cm2, was ensheathed in a 7F catheter and advanced to the occlusions under angiographic guidance. Three of four complete occlusions were recanalised in 120s or less, leaving a residual stenosis of mean (SD) diameter 54 (5)%. Ultrasound energy reduced the diameter of the isolated stenoses from 77 (14)% to 37 (21)%. All lesions were further treated with balloon angioplasty, resulting in a mean residual stenosis of 20 (9)%. There was no evidence of arterial emboli, dissection, spasm, or perforation. The major limitations of this ultrasound system are ease of steering and flexibility. Percutaneous catheter-delivered ultrasound energy appears promising for safe and effective use in atherosclerotic peripheral vessels to reduce arterial stenoses and recanalise complete arterial obstructions.